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161.
吉林省农村老龄人口人数多,增长快,是吉林省农村面临的重大问题。本文通过调查分析了农村老人社会保障存在的问题,并提出对策。 相似文献
162.
Composite samples are formed by physically mixing samples. Usually, composite samples are used to reduce the overall cost associated with analytical procedures that must be performed on each sample, but they can also be used to protect the privacy of individuals. Composite sampling can reduce the cost of identifying individual cases that have a certain trait, such as those with a rare disease or those exceeding pollution-level standards. Not much is lost by applying this method as long as the trait is relatively rare. Composite sampling can reduce the cost of estimating the mean of some process. When samples are composited, the ability to estimate the variance is lost. In spite of this, the potential savings are so great that composite samples have been used. Much of this paper deasl with the variance of estimators based on composite sampling when the porportions of hte original samples comprising the composite sample are actually random. Taking repeated samples and measurements on several composite samples complicates the prodcedure, but allows the estimation of between and within variation as well as measurement error. 相似文献
163.
Jehad Al-jararha 《统计学通讯:模拟与计算》2013,42(8):1906-1916
A class of sampling two units without replacement with inclusion probability proportional to size is proposed in this article. Many different well known probability proportional to size sampling designs are special cases from this class. The first and second inclusion probabilities of this class satisfy important properties and provide a non-negative variance estimator of the Horvitz and Thompson estimator for the population total. Suitable choice for the first and second inclusion probabilities from this class can be used to reduce the variance estimator of the Horvitz and Thompson estimator. Comparisons between different proportional to size sampling designs through real data and artificial examples are given. Examples show that the minimum variance of the Horvitz and Thompson estimator obtained from the proposed design is not attainable for the most cases at any of the well known designs. 相似文献
164.
AbstractIn this article, we have considered the problem of estimation of population variance on current (second) occasion in two occasion successive (rotation) sampling. A class of estimators of population variance has been proposed and its asymptotic properties have been discussed. The proposed class of estimators is compared with the sample variance estimator when there is no matching from the previous occasion and the Singh et al. (2013) estimator. Optimum replacement policy is discussed. It has been shown that the suggested estimator is more efficient than the Singh et al. (2013) estimator and a usual unbiased estimator when there is no matching. An empirical study is carried out in support of the present study. 相似文献
165.
Housila P. Singh 《统计学通讯:理论与方法》2013,42(23):6928-6942
ABSTRACTThis paper addresses the problem of estimation of the population mean on the current (second) occasion in two-occasion successive sampling. Utilizing the readily available information on several auxiliary variables on both occasions and the information on the study variable from the previous occasion, an estimation procedure of the population mean on the current occasion has been proposed. Theoretical properties of the proposed estimator have been investigated. Optimum replacement policy to the proposed estimator has been discussed. The proposed estimator has been compared empirically with the sample mean estimator, when there is no matching and the optimum estimator which is a linear combination of the means of the matched and unmatched portions of the sample at the current occasion. Appropriate recommendations have been made for practical applications. 相似文献
166.
Parthenia Dinora Kathleen Lynch 《Journal of social work in disability & rehabilitation》2017,16(3-4):377-395
ABSTRACTThe number of interventions available for children with autism spectrum disorder (ASD) has expanded greatly in recent years, although relatively little is known about the factors that influence family caregivers as they make treatment decisions for their children. This study involved a statewide survey of parents of young children with ASD to examine the relative weights of the factors that influenced their treatment decisions. Results suggested that caregivers rely on their own intuition for much decision making, although selected professionals are also influential. Implications for professionals working with children with ASD and their families are discussed. 相似文献
167.
Lot resubmissions are allowed in situations where the original inspection results are suspected or when the supplier is allowed to opt for resampling as per the provisions of the contract etc. This paper examines the situation of resampling of lots and derives the performance measures of a resampling scheme having a single sampling plan for inspection. The usefulness and limitations of resampling of resubmitted lots are also discussed 相似文献
168.
D. R. Cox Michelle Jackson Shiwei Lu 《Journal of the Royal Statistical Society. Series A, (Statistics in Society)》2009,172(2):483-493
Summary. Square contingency tables with matching ordinal rows and columns arise in particular as empirical transition matrices and the paper considers these in the context of social class and income mobility tables. Such tables relate the socio-economic position of parents to the socio-economic position of their child in adulthood. The level of association between parental and child socio-economic position is taken as a measure of mobility. Several approaches to analysis are described and illustrated by UK data in which interest focuses on comparisons of social class and income mobility tables that are derived from the same individuals. Account is taken of the use of the same individuals in the two tables. Additionally comparisons over time are considered. 相似文献
169.
This paper considers a class of densities formed by taking the product of nonnegative polynomials and normal densities. These densities provide a rich class of distributions that can be used in modelling when faced with non-normal characteristics such as skewness and multimodality. In this paper we address inferential and computational issues arising in the practical implementation of this parametric family in the context of the linear model. Exact results are recorded for the conditional analysis of location-scale models and an importance sampling algorithm is developed for the implementation of a conditional analysis for the general linear model when using polynomial-normal distributions for the error. 相似文献
170.
Tammy L. Henderson Maria Sirois Angela Chia-Chen Chen Christopher Airriess David A. Swanson David Banks 《Population research and policy review》2009,28(1):67-92
In 2005, the National Science Foundation funded a number of projects to study the impact of Hurricane Katrina. The current
article provides an overview of several research approaches used to conduct post-Katrina research. Each method had some advantages
and disadvantages. The post-disaster context meant that experience from traditional survey methods often did not apply. Comparisons
of advantages and disadvantages associated with each sampling method serve to inform future post-disaster research and illuminate
the limits of classical research methods. 相似文献